Aros Castle is a 13th century stone rectangular hall house and courtyard fortress, founded by the MacDougalls of Lorn. Of two storeys and a part attic, the hall stands on the north-west angle of a flat-topped promontory, with steep slopes down to the beach. The hall house commands the irregularly shaped walled courtyard and the northern landward approach across the ditch and outer bank, down to a gateway in the west wall. In the early 14th century, 'Dounarwyse' was in the possession of the MacDonald Lords of the Isles and in the late 17th century, it was garrisoned by Argylls troops. But in 1688 the castle was described as, 'ruinous, old, useless and never of any strength'. The house is buried by masonry to first floor level and projecting from the north wall, are the remaining walls of a turret. To the west and south, are the overgrown walls of the courtyard, along with turf-covered foundations of an eastern rectangular building and traces of other buildings to the north-west and south-west. 16 miles south-east is Duart Castle.

Aros Castle is located on the Isle of Mull, north-west of Salen off the A848. 9 miles south of Tobermory, on the A848.